There have been 19 Fentanyl deaths since December 28, and none appear to be related to the misuse of a Fentanyl patch, according to Medical Examiner's Office. 

There were 28 fentanyl deaths in 2015, and 16 in 2014.

It's  about 100 times more potent than morphine, and 30 to 50 times more potent than heroin. That means it's deadly even in small amounts.

RELATED LINK: Fentanyl overdose deaths on the rise in Milwaukee County

Of the 19 deaths, none appear to be related to the misuse of a fentanyl patch, but are from the illicit use of controlled substances and poly-drug abuse.

The 19 deaths are broken down as follows:  14 in the City of Milwaukee, two in Franklin, one in West Allis, and two in Cudahy.  Reports will be available after a final cause of death determination.